Arctic sea ice volume has dropped 50% faster than models predicted, according to new data from the European Space Agency's Cryosat-2 satellite that measures sea ice thickness. "Preliminary analysis of our data indicates that the rate of loss of sea ice volume in summer in the Arctic may be far larger than we had previously suspected," said Dr Seymour Laxon, of the Centre for Polar Observation and Modelling at University College.
Decline of reflective sea ice is already allowing the Arctic ocean to take up far more solar heat in the spring and summer months. Further ice loss will allow even more heat to warm the Arctic. Ice free Septembers are likely to be much stormier because high pressure will build over Siberia as the land cools while low pressure will be maintained over the relatively warm open water. Fall in the Arctic ocean is likely to become very stormy as the heat stored over the summer in the ocean fuels intense lows. Bizarre weather can be expected in the northern hemisphere as the jet stream responds to changes in the Arctic. Hurricane like polar lows can be expected to form suddenly in the late fall over open Arctic waters when cold Siberian air violently interacts with relatively warm open ocean waters.
Preliminary results from the European Space Agency's CryoSat-2 probe indicate that 900 cubic kilometres of summer sea ice has disappeared from the Arctic ocean over the past year.The Cryosat-2 data confirm the University of Washington's PIOMAS ice volume methodology that shows Arctic sea ice volume is in catastrophic decline.The exponential best fit shows that September sea ice might be gone by 2015. A linear fit to recent data might buy a few more years, but no reasonable fit of recent years data extends that milestone past 2020. Even more disturbing, the Arctic could become totally ice free before 2030 if Wimpeus' exponential fit to other months is correct.
This rate of loss is 50% higher than most scenarios outlined by polar scientists and suggests that global warming, triggered by rising greenhouse gas emissions, is beginning to have a major impact on the region. In a few years the Arctic ocean could be free of ice in summer, triggering a rush to exploit its fish stocks, oil, minerals and sea routes.
The northern hemisphere climate that we have come to know over the past 100 years will be irreversibly changed over the next 20 years by the loss of Arctic sea ice.